Abstract: Method of producing plates having an identical configuration of valleys and lugs thereon so that one plate is interchangeable with another. Flat plates are provided with a pair of individual holes at opposite ends of the plate center line. Thereafter one or more valleys are machined in a predetermined spacing and location from one or both of the locating holes, and the process repeated for a plurality of plates. Lugs are produced by matching one plate with another by means of pins inserted into the locating holes, and injecting a hardenable material into the valleys. This hardenable material is bonded to the opposite plate. The machining operation of the valleys is carried out in a manner to produce randomly spaced ridges along the side surfaces of the valleys which form depressions in the side surfaces of the lugs that are cast therefrom. Molds made from the respective pattern plates have valleys with ridges therein which have an interference fit with respect to lugs of a matching mold.

Abstract: A two part bushing or guide pin for aligning foundry flasks, hot boxes, and the like comprising: a machinable body portion having external threads for threading into a flask, hot box, etc., and internal threads for receiving either a hardened nonmachinable guide ring or a hardened nonmachinable guide pin.In the case of the hardened nonmachinable guide ring, the outer surfaces are provided with hardened ground threads adapted to be threaded into the internal threads of the main body portion. Suitable means is provided for locking the ring in angular relationship with the body after it is threaded therein. The construction permits the main body portion of the bushing to be firmly seated and locked in a flask, etc., following which the hardened ring can be rotated within the main body portion until its surfaces are accurately angularly positioned relative to the flask, and the ring then locked to the bushing.